Mozilla Foundation Security Advisory 2006-35

Privilege escalation through XUL persist.

Announced

June 1, 2006

Reporter

Jonas Sicking (Mozilla)

Impact

Critical

Products

Firefox, SeaMonkey, Thunderbird

Fixed in

Firefox 1.5.0.4

SeaMonkey 1.0.2

Thunderbird 1.5.0.4

Description

In certain circumstances persisted XUL attributes are associated with the
wrong URL. If an attacker can get a persisted string associated with an
URL that will later eval or execute that attribute in a privileged
context then the attacker's code will run with the full permissions
of the browser.

Thunderbird shares the browser engine with Firefox
and could be vulnerable if JavaScript were to be enabled in mail. This is not
the default setting and we strongly discourage users from running
JavaScript in mail.

Workaround

Disable JavaScript until you upgrade to the fixed version

References

Exploit details withheld until sufficient users upgrade to a fixed version